EP0524040A1 - Mechanism to lock an electronic board in a chassis - Google Patents

Abstract

This locking device in a chassis of the front face (2) of a drawer (1) for electronic card (s) comprises a bolt (9) slidably mounted on the front face between a locking position in a strike (11) carried by the chassis and an unlocking position, and an articulated lever (10) adapted to move said bolt (9) between said locking and unlocking positions when it is tilted respectively between a substantially folded position along said front face (2) and a gripping position in which it projects relative to said front face. The lever (10) is articulated on the bolt (9) and movable in translation with the latter, and the lever (10) and the front face (2) comprise complementary means which cooperate to move said bolt (9) and said lever (10) in translation when said lever is tilted between said folded position and said gripping position. <IMAGE>

Description

The present invention relates to a device for locking in a chassis the front face of a drawer for electronic card (s), as well as a drawer equipped with such a device.

It is known, in particular in the field of professional electronic equipment, to mount in chassis a number of drawers each comprising one or more electronic cards, for example printed circuits carrying discrete electronic components and / or integrated circuits. These chassis are generally fitted at the bottom with connectors making it possible to connect the electronic circuits contained in the cards to the outside. When they have large dimensions, these pieces of equipment may consist of a bay uniting together several frames arranged one above the other and / or one next to the other.

There are a large number of applications in which the drawers must be able to be easily put in and out of the frames. This is the case, in particular, when the drawers constitute modules having specific functions (signal processing in the audio and video field for example) which can be assembled in a large number of different combinations to meet a specific need. and temporary of a user. It is then convenient to provide on the drawers and the chassis with additional locking means which will make it possible, without using any tool, to easily handle the drawers.

Document DE-A-3 636 088 describes a locking device in which the top and bottom frames of a chassis are equipped in their front part with a keeper of a particular shape adapted to cooperate with a bolt of complementary shape carried by the front of a drawer or equivalent fitted with an electronic card. The bolt is capable of sliding perpendicular to the front face between a locking position in the keeper and an unlocking position under the effect of a lever articulated on the front face and adapted to move the bolt between the locking and unlocking when it is tilted respectively between a position substantially folded along the front face and a gripping position in which it projects relative to this same front face.

This locking device of the prior art has the drawback, however, of presenting a relatively complex and bulky embodiment which uses a housing attached to the front face and containing a lever articulated in this housing and a spring trapped in it and cooperating with the bolt to urge it elastically in a direction perpendicular to its sliding movement. In addition, the chassis cannot be of a standard model because it must be equipped at defined locations with strikes of appropriate configuration to cooperate with the bolts carried by the drawers or the like.

The expression "standard chassis" here designates a framework of generally parallelepipedal shape made up of profiles and of which at least the upper and lower profiles of the front part have a row of tapped holes regularly spaced from one another. It is conventional to fix drawers in these standard frames by means of screws received in the tapped holes through orifices provided in the upper and lower part of the front face of the drawers. Such standard chassis are naturally much less expensive than chassis specific equipped with strikes as described in patent DE-A-3,636,088, on the other hand, the method of locking and unlocking the drawers by screw proves to be much less convenient when the drawers are handled frequently.

The invention aims to provide a device for locking the front face of a drawer in a chassis which is of a simple and inexpensive embodiment, of a reduced bulk and of an easy handling. Another object of the invention is to provide a locking device which can be used with standard frames devoid of origin of any means for locking the drawers, with the exception of tapped holes or other equivalent conventional fixing means.

• ledit levier est articulé sur ledit pêne et mobile en translation avec celui-ci,
• ledit levier et la face avant comportent des moyens complémentaires qui coopèrent pour déplacer ledit pêne et ledit levier en translation lorsque ledit levier est basculé entre ladite position rabattue et ladite position de préhension. Ce dispositif de verrouillage est d'une réalisation particulièrement simple puisque le levier est porté par le pêne et mobile en translation avec celui-ci, aucune pièce n'étant ainsi articulée sur la face avant du tiroir.

To this end, the subject of the invention is a device for locking in a chassis the front face of a drawer for electronic card (s), comprising a keeper carried by said chassis, a bolt carried by said front face for slide between a locking position in said strike and an unlocking position, and an articulated lever adapted to move said bolt between said locking and unlocking positions when it is tilted respectively between a substantially folded position along said front face and a gripping position in which it projects relative to said front face, characterized in that:

• said lever is articulated on said bolt and movable in translation therewith,
• said lever and the front face comprise complementary means which cooperate to move said bolt and said lever in translation when said lever is tilted between said folded position and said gripping position. This locking device is of a particularly simple embodiment since the lever is carried by the bolt and movable in translation with the latter, no part being thus articulated on the front face of the drawer.

• la figure 1 est une vue en perspective éclatée d'un tiroir comportant un dispositif de verrouillage selon l'invention ;
• la figure 2 est une vue en perspective éclatée, à plus grande échelle, du dispositif de verrouillage équipant le tiroir de la figure 1 ;
• la figure 3 est une vue en élévation frontale du levier ou poignée du dispositif de verrouillage des figures 1 et 2 ;
• la figure 4 est une vue en coupe suivant la ligne IV-IV de la figure 3 ;
• la figure 5 est une vue en élévation frontale de la partie inférieure de la face avant des figures 1 et 2 ;
• la figure 6 est une vue en coupe suivant la ligne VI-VI de la figure 5 ;
• la figure 7 est une vue partielle en perspective du tiroir de la figure 1 en position montée dans un châssis ;
• la figure 8 est une vue en élévation frontale de la face avant du tiroir de la figure 7 ;
• la figure 9 est une vue en coupe suivant la ligne IX-IX de la figure 8 ;
• les figures 10A à 10D sont des vues en coupe partielle du dispositif de verrouillage montrant le levier et le pêne dans différentes positions de fonctionnement ;
• la figure 11 est une vue partielle en coupe longitudinale du boîtier de la figure 1 ; et
• la figure 12 est une vue en perspective éclatée similaire à la figure 1 montrant la face avant d'un tiroir selon un second mode de réalisation de l'invention.

Other characteristics and advantages of the invention will emerge from the description which follows of embodiments given by way of examples and illustrated by the appended drawings in which:

• Figure 1 is an exploded perspective view of a drawer having a locking device according to the invention;
• Figure 2 is an exploded perspective view, on a larger scale, of the locking device fitted to the drawer of Figure 1;
• Figure 3 is a front elevational view of the lever or handle of the locking device of Figures 1 and 2;
• Figure 4 is a sectional view along line IV-IV of Figure 3;
• Figure 5 is a front elevational view of the lower part of the front face of Figures 1 and 2;
• Figure 6 is a sectional view along line VI-VI of Figure 5;
• Figure 7 is a partial perspective view of the drawer of Figure 1 in the mounted position in a frame;
• Figure 8 is a front elevational view of the front face of the drawer of Figure 7;
• Figure 9 is a sectional view along line IX-IX of Figure 8;
• FIGS. 10A to 10D are views in partial section of the locking device showing the lever and the bolt in different operating positions;
• Figure 11 is a partial view in longitudinal section of the housing of Figure 1; and
• Figure 12 is an exploded perspective view similar to Figure 1 showing the front face of a drawer according to a second embodiment of the invention.

Referring to Figure 1, a drawer 1 for receiving electronic cards (not shown) has the shape of a rectangular housing comprising a front face 2, upper 3 and lower 4 sides joined to a first side wall 5, a second side wall 6, and a rear closing plate 7 optional.

The front face 2 has in the lower part a T-section groove 8 extending from its lower edge parallel to the overall plane of said front face and in which a bolt 9 can slide on which is articulated a lever 10 making also acts as a grip handle. The groove 8 is open at its end adjacent to the lower edge of the front face 2. The bolt 9 can slide in the groove 8 between an unlocked position and a locked position in which it projects into a keeper 11 intended to be fixed to the screw means 12 and 13 to a frame (not shown in Figure 1) intended to receive the drawer 1.

The front face 2 is made of electrically conductive plastic and has, above its lower part comprising the groove 8, a window consisting of a grid 14, the bars of which can be cut at will by means of a cutting pliers or the like so as to allow the positioning, at one or more desired locations behind the grid 14, of electronic components such as light-emitting diodes. The bars of the grid 14 must be small enough to be easily sectioned, while having a width sufficient to allow the bonding on the whole of the grid 14 of a label (not shown) for identification and personalization of the drawer. . The aforementioned components can be carried by a printed circuit (not shown) mounted in the drawer as will be explained below or received in a skirt 15 protruding rearward from the front face 2. The front face 2 is supplemented by a plastic door 16 comprising along one of its longitudinal edges two aligned pins 17 and 18 received respectively in housings 19 and 20 coming from molding with the front face 2 to form hinges. The door 16 can be immobilized in the closed position thanks to a stud 21 intended to be engaged elastically in a housing 22 of the front face 2.

The upper 3 and lower 4 sides are in the form of grids of electrically conductive plastic which are welded to the metal side wall 5. The sides 3 and 4 have respectively longitudinal grooves 23 and 24 facing one the other and between which is received the other side wall 6, also metallic. Optionally, the walls 5 and 6 can be fixed to the sides 3 and 4 by a set of screws designated by the reference 25.

The front face 2 is fitted by its skirt 15 onto the corresponding end of the sides 3 and 4. For this purpose, the sides 3 and 4 carry elastic tabs 26 in the form of hooks and the upper and lower edges of the skirt 15 are provided with lights 27 (see also FIG. 11) in which the hooks 26 can engage. Optionally, this snap-fastening of the front face 2 on the integral elements 3, 4 and 5 of the drawer can be completed at means of screws designated as a whole by the reference 28. In the mounted position of the front face 2, the side walls 5 and 6 are located in the extension of the side edges of the skirt 15 and are pressed against them.

As follows from the above description, the side wall 6 can be withdrawn rearwards out of the slides 23, 24 and thus give access to the interior of the drawer without having to dismantle the front face 2. The rear wall 7 , which is optional and fixed to the sides 3 and 4 by means of screws 29, does not prevent this extraction towards the rear of the side wall 6.

The sides 3 and 4 have on their facing faces a network of bosses 30 defining two sets of grooves at right angles, namely a set of 43 transverse grooves parallel to the front face 2 and a set of 4 longitudinal grooves perpendicular to the transverse grooves and on the front face 2. The drawer 1 can therefore receive electronic cards in the longitudinal direction and / or in the transverse direction. Preferably, the electronic cards are connected two by two to each other in a conventional manner by conductors embedded in a strip of plastic material and ending in connectors plugged into corresponding connectors of the cards. The cards arranged parallel to the front face 2 do not require any fixing in the drawer because they are sandwiched between the side walls 5 and 6. The maintenance of cards arranged longitudinally in the drawer 1 is ensured by the fixing of the connector integral with these cards in the drawer by means of screws 31. As a variant, if a plate 7 is mounted at the rear of the drawer, any fixing becomes unnecessary since the cards are then sandwiched between the front face 2 and the rear face 7.

Referring also to Figures 2 to 10, the bolt 9 has on one of its faces a base 32 which, when the bolt is mounted in the groove 8, protrudes through a cutout 33 of said groove. The handle 10 forms a yoke 34 and it is connected to the bolt 9 by a metal pin 35 extending through aligned holes 36 and 37 of the bolt 9 and the yoke 34 respectively.

The front edge 38 of the bolt 9 is intended to engage behind a projecting rim 39 of the keeper 11 in the locked position, while the base 32 ends on the side opposite to the front edge 38 by a projecting beak 40 adapted to limit the movement of the handle 10 beyond the gripping position shown in FIGS. 7 to 9.

The keeper 11 is pierced with two holes 41 and 42 for the passage of the screws 12 and 13 for its fixing at a desired location along a rail 43 of the chassis comprising a strip 47 provided with tapped holes (Figure 7). Its front wall has, between the holes 41 and 42, a recessed surface 44 intended to receive a label carrying, for example, identification data of the drawer intended to be placed in the chassis at the location defined by the keeper.

Each of the cheeks of the yoke 34 of the handle 10 carries a stud 45 which projects obliquely towards the rear and towards the underside of the handle 10. The two studs 45 of the handle 10 are intended to be received respectively in two recesses 46 formed in the front face 2 on either side of the T-groove 8. Each recess has the shape of a rectangular groove having at its opposite ends bosses 49 and 50 respectively projecting into the angles formed between the bottom 51 of the groove and its end walls 52 and 53 respectively.

The bosses 49 and 50 form cam surfaces, the role of which will be better understood by referring to FIGS. 10A to 10D.

In the locking position shown in FIG. 10A, the handle 10 is folded down along the front face 2 and is held in this position by the fact that each of the pins 45 is in abutment in the corresponding recess between the boss 49 and the end wall 52. Any movement of the handle 10 beyond this position in the direction indicated by the arrow F1 is prohibited by the fact that the underside of the handle is then in abutment against the front face 2. In this position, the front edge 38 of the bolt 9 protrudes from the T-groove 8. If a drawer is in position in a frame to the right of a keeper 11 as shown in Figure 7, and if the handle is in locking position as shown in FIG. 10A, the front edge 38 of the bolt 9 is engaged behind the rim 39 of the strike 11 and thus locks the drawer in position in the chassis.

To unlock the drawer, the handle 10 is tilted upwards in the direction indicated by the arrow F2, which implies the crossing of a first hard point when the end of the studs 45 passes over the top of the bosses 49. This crossing hard point occurs by elastic deformation of the different parts 2, 9 and 10, thanks to an appropriate choice of the plastic material of which they are made and their manufacturing tolerances. During the continuation of the rotation movement of the handle 10 in the direction of the arrow F2, the bolt 9 remains stationary as long as the studs 45 rotate freely in the recesses 46. When the studs 45 meet the bosses 50, the continued tilting of the handle 10 in the direction of the arrow F2 has the effect of pushing upwards, parallel to the front face 2, the hinge pin 35 and the bolt 9 linked to the latter. The movement of the bolt 9 continues until its rear edge comes to bear against the bottom of the groove 8. The handle 10 then offers resistance but, by continuing to tilt in the direction of the arrow F2, a new crossing hard point occurs when the ends of the pins 45 pass over the top of the bosses 50 by elastic deformation. The handle 10 is then immobilized in the unlocking position shown in FIG. 10C, by the fact that the end of each of the pins 45 is slightly engaged by force between the boss 50 and the adjacent end wall 53. In this position, the handle 10 extends substantially perpendicularly to the front face 2 and offers a gripping means making it easy to extract or place a drawer in the chassis. As can also be seen in FIG. 9, in this position the bolt 9 is sufficiently retracted to be able to pass over the edge 39 of the keeper 11.

The bolt 9 is mounted to slide freely in the groove 8 parallel to the front face 2 and it is retained in the latter only by the engagement of the pins 45 in the recesses 46. However, the bolt 9 can be entirely disengaged from the groove 8 continuing, from the position of FIG. 10C, the movement of the handle 10 upwards in the direction of the arrow F2 until, by elastic deformation, the pins 45 come completely out of the recesses 46 as shown in Figure 10D. To completely release the bolt 9 and the handle 10, it suffices to slide the handle 10 downwards while keeping it in the position shown in FIG. 10D until the bolt 9 comes completely out of the groove 8 as shown in particular in the exploded view of figure 1.

The establishment of a bolt 9 in a front face 2 takes place by performing the reverse operations to those which have just been described. It will also be noted that when one passes from the gripping or unlocking position (FIG. 10C) to the locking position (FIG. 10A), the descent of the bolt 9 results from the coming into contact of the pins 45 against the bosses 49, this which has the effect of pushing the hinge pin 35 down parallel to the front face 2.

The locking device which has just been described uses only a very small number of parts, namely the front face 2, the bolt 9, the handle 10, the keeper 11 and the axis 35. The axis 35 is a simple metal rod, while the front face 2, the bolt 9, the handle 10 and the keeper 11 can be made of polycarbonate plastic by an injection molding operation. The manufacture of these parts and their assembly are therefore extremely simple and inexpensive, and the possible replacement of a damaged part is particularly easy.

It will also be noted that a front face 2 only (that is to say without the elements 3, 4, 5, 6 and 7) can be locked on a frame to dress it in case it is only partially equipped with drawers. For this purpose, a hole 54 (FIG. 1) is provided in the upper part of the front face 2 to allow its fixing by means of a screw 56 in a tapped hole of a strip 48 forming part of an upper rail 55 of the chassis (figure 7). However, in order to avoid manipulation of the screws, as a variant, the front face 2 can be provided in the upper part with a second locking device identical to that described above. When the front face 2 is part of a drawer, this fixing in the upper part is not necessary since the drawer held by slides in the chassis can only move in translation.

FIG. 12 illustrates a second embodiment of the invention in which the same reference numbers as in FIGS. 1 to 11, but increased by the number 100, have been used to designate corresponding members. In this variant, the front face is intended to equip drawers having a width which is twice that of the drawers of the embodiment of FIGS. 1 to 11. However, this front face 102 has only one locking device placed next to a part 157 molded and which, for purely aesthetic reasons, has the same appearance as the locking device when the handle thereof is folded into the locked position. Preferably, this part 157 also has a keying function in the sense that a double drawer cannot be put in place in a chassis if, in line with part 157, a keeper is fixed to the lower rail 43 of the chassis. To do this, the lower edge of the front face has a rib projecting downward (which is hidden by the part 157 and therefore not visible in Figure 12). If a keeper 11 is fixed to the rail 43 to the right of the part 157, this rib abuts against the edge 39 of the keeper 11 and consequently prevents the drawer from being fully engaged in the chassis.

It goes without saying that the embodiments described are only examples and they could be modified, in particular by substitution of technical equivalents, without departing from the scope of the invention. Thus, for example, that the groove 8 can be formed between a flat part of the front face 2 and an insert and fixed on the latter by any suitable means such as gluing, screwing, etc.

Claims (12)

Device for locking in a chassis the front face of a drawer for electronic card (s), comprising a keeper carried by said chassis, a bolt carried by said front face for sliding between a locked position in said keeper and a unlocking position, and an articulated lever adapted to move said bolt between said locking and unlocking positions when it is tilted respectively between a position substantially folded along said front face and a gripping position in which it projects relative to to said front face, characterized in that: - said lever (10; 110) is articulated on said bolt (9; 109) and movable in translation with the latter, - said lever (10; 110) and the front face (2; 102) comprise complementary means (45, 46) which cooperate to move said latch (9; 109) and said lever (10; 110) in translation when said lever is tilted between said folded position and said gripping position. Device according to claim 1, characterized in that said bolt (9; 109) is slidably mounted in a groove (8; 108) formed on said front face (2; 102) from an edge thereof. Device according to claim 2, characterized in that said complementary means comprise at least one stud (45) projecting from said lever (10; 110) and two cam surfaces (49, 50) formed on said front face (2; 102 ), said stud (45) being adapted to bear against said cam surfaces and push said lever and said bolt into said locking and unlocking positions when said lever (10, 110) is tilted respectively in said folded and gripping positions . Device according to claim 3, characterized in that said cam surfaces are constituted by two bosses (49, 50) adjacent respectively to two opposite ends (52, 53) of a housing of said front face (2; 102) and cooperating with said stud (45) to form two hard points for holding said lever (10, 110) respectively in said folded and gripping positions. Device according to claim 4, characterized in that said stud (45) and said housing (46) constitute means for retaining said bolt (9; 109) in said groove (8; 108) and in that said stud (45) is shaped to be released by elastic deformation out of said housing (46) by tilting of said lever, beyond said gripping position, towards a bolt release position, and engaged by elastic deformation in said housing by tilting of said lever towards said gripping position, from said bolt release position. Device according to any one of claims 4 and 5, characterized in that said front face (2) comprises two housings (46) formed on either side of said groove (8) and the lever (9) carries two pins (45) adapted to cooperate respectively with said housings. Device according to any one of claims 2 to 6, characterized in that said lever is articulated on a base (32) of said bolt (9) adapted to project through a cutout (33) of said groove (8). Device according to any one of claims 1 to 7, characterized in that said keeper (11) is a removable part fixed to said chassis. Device according to claim 8, characterized in that said keeper (11), said bolt (9), said lever (10) and said front face (2) are molded plastic parts. Drawer for electronic cards intended to be slidably mounted in a chassis, characterized in that it comprises at least one locking device according to any one of claims 1 to 9. Drawer according to claim 10, characterized in that it comprises an upper side (3) and a lower side (4) provided with orthogonal grooves (30) for the selective mounting of electronic cards parallel and perpendicular to said front face (2) . Drawer according to claim 10, characterized in that said front face (2; 102) is snap-fastened to at least one side (3, 4) of said drawer.

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